Vaned blower



F611 4, 1954 D. L. ENDlcoTT ETAL 3,120,191

VANED BLOWER Filed Feb. 5, 1961 3 Sheets-Sheet 2 /6 United States Patent O 3,12%51 VANED BLGWER Donald L. Endicott, Berkley, and William H. Kir-lr, l.Gilarren, Mich., assignors to Curtiss-Wright Corporation, Utica, Mich., a corporation of Delaware Filed Feb. 6, 1961. Ser. No. 37,177 3 Claims. (Cl. 163-1135) This invention relates to rotary vane pumps in general and more particularly to pumps of this type for use as small vaned blowers.

Most presently known varied blowers and pumps are limited in capacity, per unit size, to the permissive extension of the vane members from the rotor housing. Where such varies extend radially outward from the rotor their extended length is less than the radius of the rotor, since a bearing surface must be retained. Other arrangements which have been proposed have been overly complicated and too expensive to manufacture and/or repair and in many instances other complications have arisen in the use of other vane arrangements.

lIhe means employed to assure full extension of the rotor vanes have included unduly complicated back-up spring devices and the like or, in some instances, have required the use of heavier vane structures than necessary; in order to take full advantage of centrifugal forces acting thereon. The latter, in turn, introduces problems of wear and continuous lubrication.

Although of somewhat lesser consequence in comparison with other problems, the pressure loss in blower devices across the rotor bearings and/or the pressure gradient on opposite sides of the bearings is a factor under constant surveillance.

lt is an object of this invention to provide a vane pump structure particularly suited for use as a vaned blower.

lt is also an object of this invention to provide a vaned blower structure having a rotor and vaned members cooperatively formed for greater radial extension thereof than within like blowers of comparable size.

Another object of this invention is to teach means of eliminating the need for overly heavy vane members wholly responsive to the edects of centrifugal force7 or the need for complicated back-up springs and the like, to maintain vane sealing contact with the blower housing walls.

Still another obiect of this invention is to teach vane guiding and pressure balancing means enabling the use of lighter weight, longer life, frictional resistant varies and minimizing the lubrication requirements normally expected.

A further object of this invention is to teach fluid pressure means of vane extension and pressure balancing and to mal-:e use of the exhaust uids through bleed-back passageways and chambers.

A still further object of this invention is to make use of bleed-back duid pressures to eliminate the pressure gradient and losses across bearings to increase the life expectancy thereof.

These and other objects will be more apparent upon a reading of the specitication which follows in conjunction with the accompanying drawings wherein:

FIGURE l is a plan view of a vane blower made in accord with the teachings of this invention and having parts broken away and shown in cross-section for better illustration thereof.

FGURE 2 is a cross-sectional end View of the vane blower of FGURE. `l, as seen in the plane of line 2-2 thereof and loolring in the direction of the arrows thereon.

FIGURE 3 is a cross-sectional view of the vane blower of FEGURES l and 2 as seen substantially in the plane of line v3 3 of FlGURE 2.

Frice FGURE 4 is a cross-sectional view through bleed-back passage means of the hereinafter described blower, as seen in the plane of line 4 4 of FIGURE l.

FlGURE 5 is a cross-sectional view through the vane blower as seen substantially in the plane of line 5 5 of FiGURE 2.

Referring to the drawings in further detail:

The vaned blower lil includes a housing 112. having a chamber 14 provided therein. The chamber -14 is cylindrical in shape and is closed at the ends thereof. An inlet opening 16 and an outlet opening 1S are provided through the housing intermediate the ends of the chamber space iid.

A rotor Ztl is eccentrically mounted within the chamber space ld and is provided with rotor vane members 22;. rl'he rotor 2G includes shaft ends 24 which are journalled within end ybearings 26 provided within the end walls of the housing l2.

The rotor 20 includes a hub portion 2S disposed within the chamber area ldand extending the length thereof. In the present instance, the hub portion 2S is triangular in cross-section and includes chord faces 3b to which lobe members 32 are secured.

lln subsequently describing this invention, it will be appreciated that other than the tri-lobe arrangement disclosed may be used in practicing the teachings of this invention, IFurther, since the :rotor construction is symmetrical similar numeral designations have been used in describing similar parts thereof and would apply equally to any polygonal configuration. The tri-lobe arrangement has been selected for illustration since it is the more simple and most suitable congniration for blower application being described.

The lobe members 3-2 are secured by fastening means 34 to mounting faces 36 provided on the chord faces 3l? of the rotor hub 28. The mounting faces 36 are raised rom the surface of the chord faces 3l? and serve as guiding posts for the rotor vane members 22, as will be subsequently shown.

The lobe members 32, as secured to the rotor hub 2S, form in combination a cylindrical rotor body. The lobe members 32. each include an end 3S which overhangs the rotor hub 2S and an undercut end 4@ providing an end face in the plane of the chord face 3Q of the rotor hub. The adjacently disposed ends of the different lobe members 32 are accordingly relatively spaced to provide a vane receptive space 42 therebetween.

The rotor vanes ZZ may be of any suitable lightweight construction. As will be shown, the vane members are not dependent solely upon the effects of centrifugal force to attain their fully extended position. Por best performance the vanes are made of materials having good rubbing and structural properties for the surface and core thereof, respectively. ln the present instance, although not specifically shown, a core of fiberglass-phenolic is used to provide strength and a phenolic impregnated nylon cloth is bonded thereto to provide good dry rubbing characteristics. A tuft of nylon cloth is also arranged at the tip of the vane for better wear characteristics at such location.

The rotor vanes 22 are of rectangular configurations and formed to include side extensions 4dand 46 which provide a chamber space 4;3 therebetween.

The vane members 22 are received within the vane receptive space 4Z between the ends of adjacent lobe members 32 and the side extensions d4 and 46 are received about the guiding post 36 to which the lobe members 32 are secured. The side extensions 44 and 4.6 provide both the bearing surface and guide means which enables more complete extension of the varies within the chamber space 14.

The vane members 22 are constantly urged to their 3 fully extended position by air pressure introduced within the chamber space 48 between the vanes and the guiding posts 36 of the rotor hub 28.

A bleed passage 50 is formed through the housing 12 and connects to a chamber 52 in communication with one of the rotor shaft ends 24. A passage 54 is provided through the one shaft end and connects to passages 56 through the rotor hub and in communication with passages 58 provided on the underside of each of the lobe members 32. This is best shown by FIGURE 5.

The lobe passages 58 are in communication with the chamber space 4S between the side extensions 44 and 46 of the rotor vanes 22. In addition, the lobe passages S8 include extensions 60 formed to extend over the Vside extensions 44 and 46 ofthe vane members.

In the course ofblower operation, air pressure returning through the'bleed passages 50, 54, 56 and 58 is effectively introduced into the chamber space 48 to hold the rotor vanes in engagement with the walls of the chamber 14. Obviously, such pressure is no deterrent to the retraction of the vane members 22 within the Vanereceptive space 42 as is required in the course of rotor rotation.

Y The lobe passage extensions 60 which are exposed to the vane extensions 44 and 46, afford a balancing pressure which offsets the frictional drag on the extended ends of the vane members 22 by holding the vanes lightly seated against the ends 40 of adjacent lobe members and minimizing the frictional retardant otherwise incident to cooking of the vanes. Accordingly, the vanes are afforded free or reciprocal movement and longer life than would otherwise be obtained.

Suitable flanges 62 are provided on the rotor shaft ends 24 to close the ends of the vane receptive spaces 42 provided between adjacent lobe members 32. However, as in most rotary seals, air pressures within the chamber space 14 eventually nd their way past the sealing flanges 62. To offset the resulting pressure gradient across the end bearings 26, the bearing receptive wall 64 includes a pressure equalizing passage 66 therethrough. f

It will also be appreciated that the vane actuating pressure within the chamber space 52 will be introduced through the labyrinth passageways 68 about the one shaft end 24 and in communication with the bearing receptive space. The passage 66 likewise assures an equalization of .the pressure as regards this effect.

The operation of the disclosed vaned blower is as follows:

In the course of rotor rotation, the pressure build-up Within the housing outlet 1S is returned through passages 50, 54, 56 and 58 to the chamber space 48 enclosed by the side extensions 44 and 46 of the different vane members 22. YSuch pressure holds the vane members 22 extended for sealing engagement with the walls form-y ing the housing chamber space 14. As thel rotor rotates, the vanes 22 are retracted withinV the vane Vreceptive space 42 against the resistance of the pressure within the chamber space 48 between the vane extensions.

The vane is properly guided for reciprocal movement by the guide posts 36 which tit within the re-entrant between the vane extensions 44 and 46.

The lobe passage extensions et?, as mentioned, afford pressure balanced seating of the vanes against one of the ends of the lobe members and avoids frictional resistances which might otherwise occur.

The lighter construction aorded the rotor vanes 22, and the pressure balanced seating thereof, minimizes lubrication requirements and, with vanes of selflubricating characteristics, whichY are practicalV in the construction disclosed, lubrication considerations are at an absolute minimum.

It Will be appreciated that while a preferred embodiment of this invention has been sho'tvn and described, certain modifications and improvements are foreseeable. Such of these modifications and improvements as are within the spirit of this invention are to be considered as inclusive 'within the claims which follow, unless such claims by their terminology are exclusive thereof.

We claim:

1. A rotary pump for air compression and other uses, and comprising: a housing having a uid receptive chamber provided therein anda rotor member eccentrically mounted within said chamber, said rotor member being formed to provide a plurality of vane receptive chordal passageways and having vane guides provided therein, vane members disposed within said vane receptive passageways and having inwardly disposed side extensions guiding on said vane guides and providing a duid retaining chamber space Vtherewith and between said extensions, andV fluid pressure receptive passageways formed through said rotor and at least Yin part through said vane guides and in communication with the chamber space of said vane members for fluid pressure extension thereof.

2. A rotary pump, comprising: a housing having a fluid receptive chamber provided therein and a rotor member eccentrically disposed within said chamber, saidV rotor including a shaft having the ends thereof journaled within said housing and a hub portion disposed within, said chamber, chordal faces provided Yon said hub, lobe members adapted to be secured to said hub portion and forming in combination a cylindrical rotor body mem- Y lobe member undercut to avoid interference with the extended end of the preceding lobe member and to provide an extension of said'rotor vane passageways, rotor vane members receivedV in said passageways and guided about said lobe receptive mounting face, said vane memers ,having extended sides disposed inwardly and on opposite sides of said mounting faces, said extended sides providing a chamber space behind said vane members, and passage means provided successively from the outlet side of said housing uid chamber through said housing, rotor shaft, hub'por'tion, mounting faces and lobe members for communication with said vane chamber space.

3. The rotor pump of claim 2 having said passage means last mentioned exposed through said lobe members withinthe extended ends thereof, said extended ends being on the reduced pressure side of said vane members in the normal operation of said rotor bodyV memberv within said housing, and said lobe passage means being extended axially'over the side faces of the rearwardly disposed and guiding extensions of said vane members.

References Cited in the iile of this patent UNITED STATES PATENTSv 1,296,500 Frodsham Mar. 4, 1,358,176 Rolafi Nov. 9, 1920 1,776,921 Moessinger Sept. 30, 1930 1,855,708 Dilg Apr. 26, 1932 2,658,456 Wahlmark Nov. 10, 1953 2,763,216 Klessig Sept. 18,1956

FOREIGN PATENTS 66,806 Austria Oct. 10, 1914 407,985 Italy Dec. 16, 1944 653,295 Great Britain May 9, 1951 830,460 German,7 Feb. 2, 1952 

1. A ROTARY PUMP FOR AIR COMPRESSION AND OTHER USES, AND COMPRISING: A HOUSING HAVING A FLUID RECEPTIVE CHAMBER PROVIDED THEREIN AND A ROTOR MEMBER ECCENTRICALLY MOUNTED WITHIN SAID CHAMBER, SAID ROTOR MEMBER BEING FORMED TO PROVIDE A PLURALITY OF VANE RECEPTIVE CHORDAL PASSAGEWAYS AND HAVING VANE GUIDES PROVIDED THEREIN, VANE MEMBERS DISPOSED WITHIN SAID VANE RECEPTIVE PASSAGEWAYS AND HAVING INWARDLY DISPOSED SIDE EXTENSIONS GUIDING ON SAID VANE GUIDES AND PROVIDING A FLUID RETAINING CHAMBER SPACE THEREWITH AND BETWEEN SAID EXTENSIONS, AND FLUID PRESSURE RECEPTIVE PASSAGEWAYS FORMED THROUGH SAID ROTOR AND AT LEAST IN PART THROUGH SAID VANE GUIDES AND IN COMMUNICATION WITH THE CHAMBER SPACE OF SAID VANE MEMBERS FOR FLUID PRESSURE EXTENSION THEREOF. 